WATER AVAILABILITY OF COHESIVE SOIL UNDER THE ACTION OF POLYACRYLAMIDE: ENVIRONMENTAL PHYSICAL QUALITY

Abstract

The Coastal Trays have cohesive layers of soils that alter the state of the water in their pores, interfering in the development of the root system of the plants. This study aimed to evaluate the action of polyacrylamide and gypsum conditioners on the cohesive soil of Pernambuco Coastal Traps via the least limiting water range (LLWR). The samples were subdivided into three treatments — T0 (Control), T1 (Polyacrylamide) and T2 (Polyacrylamide + Gypsum) —, with four replicates per treatment. The water retention characteristic curve; soil density; soil resistance to root penetration (RP) and LLWR were evaluated. The means were submitted to ANOVA and Tukey’s test, by the Statistical Analysis System (SAS) application. The LLWR was efficient in detecting changes in soil water availability; being the treatment with polyacrylamide which promoted greater increase of this availability, being the critical value of the RP for the LLWR of the cohesive soil studied above 2 MPa.